The AlignWithSymbol Padding choice forces all imported stocks to have the same set of bar dates as the PadAlignSym stock by adding missing bars and removing extra bars.
This alignment is performed within the existing date range of each stock, so no bars are added before the start of its data. The most recent missing bars are, however, filled forward to the latest import date (bounded by the PadTrailMaxDays setting), so bars can be added after the end of a symbol's own data.
Since this setting is always simply one symbol, it should not be preceded by a $ as is normally done to reference a symbol within a formula.
Like Padding, this can be specified per DataPath rather than only at the Import-block level, so each DataPath can align to its own reference symbol.
